Japan Utility Struggles to Maintain Power Levels

ENLARGE

Lights were turned off to save energy before rolling blackouts in Tokyo Thursday.
Reuters

By

Juro Osawa

Updated March 17, 2011 1:47 p.m. ET

TOKYO—Tokyo Electric Power Co. is struggling to maintain stable electricity supplies for millions of people even though it has lost a major source of power, at the same time it is trying to cool down its damaged Fukushima Daiichi nuclear plant.

The Japanese government Thursday warned of a possible large-scale, unpredictable power outage in Tokyo. If the Japanese utility's power supply fails to meet demand and results in a power outage, that would be the first-ever case in the company's history, said company spokesman
Naoki Tsunoda.

While Japan's trade ministry said the greater Tokyo area—the nation's crucial economic center—will likely avert a major blackout for the rest of the day, as the use of electricity has fallen since Thursday morning after the government called on the public to save power, the fact remains that a big jump in power use could cause a blackout.

Electricity use jumped Thursday morning as cooler temperatures prompted people to use more heat, threatening to surpass Tepco's supply limit of 33.5 million kilowatts.

Tepco's supply has been cut short by about a quarter, after several power plants, both nuclear and thermal, were suspended after being hit by the massive quake and tsunami last week.

"Because we can't really increase supply, the only way we can continue to prevent a blackout is to keep power consumption lower," said Mr. Tsunoda.

The Fukushima Daiichi and Daini nuclear plants together account for about 14% of Tepco's total output. After the quake and tsunami, four thermal power facilities in Fukushima, Ibaraki and Kanagawa Prefectures remain suspended.

The halts in output from those nuclear and thermal plants has cut Tepco's supply capacity by about 25%.

Tepco experienced a large-scale power outage in 2006,after a crane ship cut off one of the company's power cables. In the past, Tepco sometimes has had difficulties meeting demand, but other regional power companies usually helped secure enough supply.

But this time, regional utility firms, particularly Tohoku Electric Co., were hit hard by the quake and have no electricity to spare.

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